Although the basic elements of large-scale semiconductor integrated circuits are mainly MOSFETs (Metal-Oxide-Semiconductor Field Effect Transistors) in the current state of the art, it has become difficult to downscale MOSFETs to improve the performance, reduce the power consumption, etc.
Therefore, research and development is being conducted for tunnel FETs (Field Effect Transistors) that utilize the tunneling of electrons unlike the operation principle of MOSFETs.